Controlled Current Source with microcontroller

Thread Starter

enes246

Joined Nov 30, 2016
10
Hi everyone,
I need a current source for my project. I must controlled average output currnet value and dirrection of the current. The average output current value range is 0-5A. input voltage 10V or 5V, switching frequency 50kHz or higher value.

I think that, I can use the full bridge inverter. By this way I can control the direction of the current easly also by changing duty cycle I can control the output value of the average current.
I can read the output current with microcontroller and I can use the PI controller to arange the duty cycle.

in here I have some question;
I do not know load value, it can be very small, so Can I control the average output current with PWM signal?
do you think this is appropriate?
Do you have any other suggestions?
 
Last edited:

mvas

Joined Jun 19, 2017
539
"On" amps = 10,000 amps = 10 Volts / 0.001 Ohms
"Off" amps = 0 amps
Average amps = 5 Amps

On-Amps will be very high, while On-Time will be very short ...
 

AnalogKid

Joined Aug 1, 2013
10,986
Your numbers make zero sense. What is it you are trying to achieve? What does the system do? What is the load that you think has resistance so small it is almost a superconductor? Take another swing at the question. Please post a sketch of what you are doing.

ak
 

Kjeldgaard

Joined Apr 7, 2016
476
If we talk about 5 amps from a 5 volt supply and to a load resistor going towards 0 Ohm, then I will vote for an analog solution.

Up to 25 watts must be dissipated in the regulation, but pulse width control does not usually fit very well with super low load resistors.
 

Ya’akov

Joined Jan 27, 2019
9,068
Your numbers make zero sense. What is it you are trying to achieve? What does the system do? What is the load that you think has resistance so small it is almost a superconductor? Take another swing at the question. Please post a sketch of what you are doing.

ak
I was wondering where he got the magic wire myself...
 

mvas

Joined Jun 19, 2017
539
Hi everyone,
I need a current source for my project. I must controlled average output currnet value and dirrection of the current. The average output current value range is 0-5A. input voltage 10V or 5V, switching frequency 50kHz or higher value.

I think that, I can use the full bridge inverter. By this way I can control the direction of the current easly also by changing duty cycle I can control the output value of the average current.
I can read the output current with microcontroller and I can use the PI controller to arange the duty cycle.

in here I have some question;
I do not know load value, it can be very small ( may be 0.0001 ohm), so Can I control the average output current with PWM signal?
do you think this is appropriate?
Do you have any other suggestions?
Are you trying make a 50 khz Switch Mode Power Supply that is a "Constant Current" source, rated 10 amps Max, allowing 5 Amps continuous ( average ) through your 0.0001 ohm load ?

Something like a 10 amp Constant Current ( LED or Battery Charger ) Switching Converter design?
 
Last edited:
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